Tank unit with internal pump and valve



1952 H. H. SCHMIEL TANK UNIT WITH INTERNAL PUMP AND VALVE 4 Sheets-Sheet. 1

Filed 001:. 23, 1946 fiERBER'I H-SCHMIELL Dec. 16, 1952- H. H. SCHMIEL TANK UNIT WITH INTERNAL PUMP AND VALVE 4 Sheets-Sheet 2 Filed 001:. 25, 1946 RBERT I'LSCHMIEL abtovmq 1366- 1952 H. H. SCHMIEL TANK UNIT'WITH INTERNAL PUMP AND VALVE 4 Sheets-Sheet 3 Filed Oct. 23, 1946 HERBERT a. SCHMIEL awn/wags Dec. 16, 1952 H. H. SCHMIEL 4 2,

TANK UNIT WITH INTERNAL PUMP AND VALVE Filed 001;. 23, 1946 v 4 Sheets-Sheet 4 JNVENTOR. fiERBfiRT a. swam E BTTORNEYS Patented Dec. 16, 1952 TANK UNIT WITH INTERNAL PUMP AND VALVE Herbert H. Schmiel, Cleveland, Ohio, assignor, by mesne assignments, to The New York Air Brake Company, New York, N. Y., a corporation of New Jersey Application October 23, 1946, Serial No. 705,051

19 Claims.

This invention relates to packaged hydraulic unitsofthe ,;combin,6.d1 pump, control'valve and tank type, and more particularly to such units where both thepump andvalve are submerged in the liquid in the tank which is used for oper- -..ating the hydraulic system.

It is a general object of the present invention to provide ,a novel and improved pump. valve and tank unit asembly of the type described.

More particularly it is an object of the invention to provide, in a unit assembly of the type described, an extremely simplified arrangement for reversing the pump passages to permit of reversal of direction of rotation of the pump.

An important feature in connection with the above object resides in the construction of the pump with one of its end plates constituting an essential portion of one of the side walls of the tank, with the pump and side wall portion symmetrical about vertical and horizontal axes,

whereby the pump end-cover plate may be rotated 180 in its plane to reverse the passage connections and hence the direction of operation. of the pump gears for coordinating the system.

Another important feature of the invention consists in the mounting of the hoist and lower valve beneath the lid or cover plate of the tank and in arranging for its connection to the pump discharge passage, to hoist ports in the cover and for the discharge of return liquid to' improve the cooling operation of the whole system.

A feature in connection with the last mentioned object resides in so returning the liquid from the hoist, or from the pump discharge, to the valve manifold and the delivery of the liquid from this manifold beneath the liquid level in the whole as a unit for service or inspection.

f Other and further features and objects of the invention will be more apparent to those skilled in the art upon a consideration of the accom- 'panying drawings and following specification wherein is disclosed a single exemplary embodiment of the invention with the understanding that such changes and modifications may be made therein as fall within the scopeof the 1 appended claims without departing from the spirit of the invention. In said drawings: Fig. 1 is a front elevation of the assembled tank unit including the pump, the control valve and the removable cover, a portion of the unitary tank wall and other parts being broken away to better illustrate certain internal features;

12 Fig. 2 is a sideelevation, with parts of the side wall of the tank broken away, to illustrategthe pump arrangement and the1 valve location and with portions of. the pump and valve housings in vertical section; r

Fig. 3 is a: top plan view of the assemblyillustrating the alternative hoist ports at two edges of the cover;

Fig. 4 is' afragmentary vertical section taken on line 4-4 of Fig.1; and

Fig. 5 is a fragmentary vertical section taken on line 5-5 of Fig. 3 and showing the valve housing and valve plunger only.

Hydraulic systems for the operation of simple hoistsor farms have developed over a period of years and are in common usage now, particularly in connection with internal combustion engines as mounted on tractors or similar'devices, for the manipulation and control'of agricultural, earth moving or other attachments or implements. Such tractors and their power units vary considerably in construction and arrangements and particularly where remotely acting power take-offs are used for driving the pump of the hydraulic system. The principal differences reside in the direction of rotation of this takeoff. This complicates the installation problem if there is no simple way to rearrange the piping to permit the pump to be driven in the direction required by the power takeoif. In the "earlier systems where thepump, tank and control valve were individual units separately mounted and piped into the system, no complications occurred, since the mere transfer of the inlet and discharge pipes of the pump solved: the whole problem. With the advent of the packaged unit, in which the whole system except the hoist and its connecting pipes is assembled into a single structure, the problem of reversible pump rotation added a considerable complication. The present invention contemplates a pump and valve both submerged in the tank and provides for a simple method ofreversing the direction "of rotation of the pump and the direction'of movement of the fluid from it without requiring any changes in the tank, pump, piping or the control valve. No external piping is used and substantially all ducts, passages or the like are cored into the castings for simplicity and economy of manufacture.

Referring now to the drawings, for a better understanding of the invention, it will be noted that the tank I0 is a unitary casting, and is substantially rectangular in plan, elevation and end view. The cover I2 is a separate casting generally convex in form and meeting the top of the tank in a horizontal peripheral surface l4 appropriately gasketed to prevent leakage. Substantial fastening members I 5 passthrough holes in the edge of the cover'and are threaded into reinforcements on the inner rim of the-wall of the tank for holding the parts securely and accurately together for a purpose which will presently appear.

As seen in Fig.2, the rear wall N of the tank is substantially flat and vertical; the bottom wall I! is flat and horizontal, while the front wall is broken and includes an upper broad, flat vef-f tical portion 18, a horizontal offset portion I9 and a vertical portion 28 inset somewhat from 18. The portion is a removable plate substantially rectangular in form, as seen in Fig. 1, and closing an opening in the lower side of the tank only slightly less in dimensions than the overall size of the cover. A suitable gasket applied between the plate and the rim of the opening insures a fluid tight connection and appropriate sturdy fastening means 2| securely attach the plate to the Side of the tank.

The plate 20 is in effect an integral enlargement of the cast end flange of a housing for a pump device which includes the main body part 23 and the rear cover plate 24. As seen in dotted outline in Fig. l, the pump is of the two gear type and of generally conventional form, having the lower or drive gear 25 and the upper or driven gear 21 pocketed in appropriate chambers in the main housing. At the junctions of these chambers are formed intake and discharge pockets 28 and 29, merging respectively into curved passages 30 and 3! symmetrically arranged as seen, the inlet one shown ending in a counter bore 33 with the opening near the bottom of the must be driven counterclockwise, as viewed in Fig. l, toinsure discharge through passage 3i. This shaft is adequately journalled in a bearing extension 36 integral with the plate 20 and terminating in a wide mounting flange 3T drilled as shown to receive attaching studs for supporting the whole tank unit from its parent machine.

If the prime mover is of the type requiring clockwise rotation of the pump drive gear, then this is readily achieved by removing the cover plate 20 and its attached pump and rotating it 180 in its own plane and remounting. The cover plate-and pump mounting are symmetrical about the horizontal-axis 38 and about the vertical axis 39 so that when-the position is changed as just described the discharge outlet 34 becomes the inlet and vice versa. The spline drive shaft and ,its mounting flange move up to a higher position as shown in'dot and dash lines in Fig. 2, but otherwise the unit is similar in appearance to before a the change.

Either of the pump counterbores 33 or 34, when positioned in the upward position, is adapted to receive with a press or other suitable machining. The valve tossing is' thus supportedin horizontal position just beneath and from the cover and may be removed with the cover by the mere separation of the pressed fit M at 34.

has its botto'i'nwall vertically bored as at 4| to re'ceive the coupling pipe 40, previously described.

. Immediately below the chamber '4'! and connected thereto is a cartridge type relief valve passage 51 leading to low pressure manifold 58 forming an integral part of the valve housing as seen in' Figs. land 5. V This manifold also receives the discharges from the low pressure relief valves, such as shown at 6B, which maintain pressure-in the end chambers 62 and 63 of the valve housing for holding the control plunger H30 in either of its hoist positions as defined in the Kirkham patent. The manifold 58 also takes the pump discharge from passage 64 during the time ports I01.

oblique fitting '66 extending from its bottom wall and a discharge tube 61,.which is inclined downwardly and'has clipped end 68 closely adjacent t the side wall of the tank whereby the circulated and returned liquid is directed against this wall to permit improved heat transfer to the sliding fit a discharge tube or pipe 40 leading ver-' tically upwardly and having a suitable fit in the inlet port 4! in the control valve housing 43. This housing is a unitary casting having hoist ducts in appropriately surfaced bosses 44 for cooperation with oppositely directed depending" bosses 45in the lid or cover 12, whereby the two may be secured together by suitable fastenings 46 and fluid tight joints between passages and ducts in the two parts be provided as will later appear. The meeting surfaces of the bosses are in the same plane as the cover rim for ease in atmosphere to maintain the liquid at a suitable low temperature under all conditions of operation.

The dishedhollow cover 12 for the tank not onlysupportsthe control valve housing 43 but provides also the external outlets for the hoist 'ducts of the valvewhereby pipes may be connected tolead to a, hoist unit for handling the liquid for actuating the same. As viewed in Fig. 3 the cover is provided on the left and lower edges with outwardly facing bosses 10, H, 12 and 13, cast integrally with the cover and raising the thin edges at these portions to the maximum height of the cover as seen in the upper left in Fig. 1. Each of these bosses is drilled as shown and internally threaded to receive a pipe leading to a hoist. The hoist bosses are provided in pairs, thus 70 and 13 are arranged for alternative use, as are H and 12. This permits piping to with a duct in the boss 45 to the right and on the :under surface of the lid, whichcooperates with the corresponding duct in'the top face of "manipulating the valve; stub' shaft 84 is fitted with a lever 81 having a forked end, the furcati ns'BB of which closely "the control valve housing. In alike manner the right angled duct I5 connects the bores of bosses II and I2 and the duct of the corresponding boss 45 on the under side of the cover. In Figs. 1 and '5 is seen at I6 a recess in each of the bosses 44 I for receiving sealing rings to insure fluid tight connections between the abutting bosses on the under side of the cover plate and those on the top face of the valve housing.

The valve housing contains a controlling valve between which is journalled a roller 82 by means of pin 83. A rotatable stub shaft 84 is journalled in a vertical bore in an appropriate bushing 85 in the tank cover and'has an upper end 86 extending :beyond the cover surface for engagement by a suitable lever and linkage means for Within the tank this straddle the'roller82 so that a partial rotation of stub shaft 84 serves to reciprocate the valve "plunger to any of the desired manipulative positions thereof.

The operation of the control valve will be clear from Fig. 5. In the central position shown liquid from the pump enters through IOI and passes through grooves I02 in the plunger to 64 and 5'! to the tank so that the pump is not loaded. If the plunger is moved to the left or right so that its central land I03 closes the corresponding passage between I and 64 then the end land on the plunger closes the similar passage on the other side. Liquid from the pump then flows in through the proper ports I04 in the plunger wall, lifts the check valve I05 and flows out the plunger-ports I06 in register with power port 'I0I to actuate the hoist. Fluid from the opposite side of the hoist returns to the other power port I0I' and around the end of the end land, which has moved toward the center, to fill the end chamber I08 of the valve housing. As long as this return liquid flows it exerts a, sufilcient pressure on the end of the valve plunger or on the annular area I09 thereof to oppose the action of the plunger centering spring H0 and the plunger is held in operating position. The returningliquid presses open appropriate plunger II2 against its spring and escapes to the return .duct 58. When return liquid ceases to flow valve H2 closes and the chamber through seepage port II3 so that the centering ,spring returns the valve plunger I00 to the neu- I08 is drained use Witha hydraulic hoist comprising in combination, a tank for holding hydraulic liquid, a removable wall forsaid tank symmetrically arranged to be applied to the tank in either of two positions, a, rotary pump mounted on said Wall'- for submersion in the liquid in the tank and having an operating shaft extending through said wall, symmetrically disposed ported passages on saidpump and. each usable as inlet or discharge dependent on the direction of rotation of the said:

shaft, a control valve'mounted independent of said wall submerged in the liquid in the tank and having an inlet port, and means to automatically connect said inlet port to one or the other of said ported pump passages dependent on the position of mounting of said removable wall on the tank whereby either direction of pump rotation may be effective to supply said valve.

2. The unit as defined in claim 1 in which the removable wall is a side wall.

3. The unit as defined in claim 1 in which th removable wall is a side wall, a removable cover for the tank and means mounting the control valve on the inner face of said cover.

4. In a unit of the type defined, in combination, a tank for hydraulic liquid, a rotary pump: submerged in the liquid and having ashaft passing through a wall of the tank, an-inletduct anda discharge duct for said pump interchangeable in use when the shaft rotation is reversed, a control valve in the tank having an inlet tube adapted for direct cooperative engagement with the active discharge duct of the pump, and means mounting the pump for change in position to engage the active discharge duct the cooperative engaging valve part to coordinate with direction of pump rotation.

5. In a unit of the type defined, in combination, a tank for hydraulic liquid, a rotary pump submerged in the liquid and having a shaft passing through a wall of the tank, an inlet duct and a discharge duct for said pump interchangeable in use when the shaft rotation is reversed, a control valve in the tank having an inlet tube adapted for direct cooperative engagement with theactivc discharge duct of the pump, a discharge tube for said valve extending within the tank to discharge against a side Wall thereof, means mounting the pump for change in position to engage the active discharge duct the cooperative engaging valve part to coordinate Withdirection of pump rotation, and means to conduct valved liquid through a wall of said tank for external use.

6. In a unit of the type defined, in combination, a tank for hydraulic liquid, a rotary pumpsubmerged in the liquid and having a shaft passing through a wall of the tank, an inlet duct and a discharge duct for said pump interchangeable in use when the shaft rotation is reversed, a control valve in the tank having an inlet tube adapted for direct cooperative engagement with the active discharge duct of the pump, means mounting'the pump'for change in position to engage the active discharge duct the cooperative engaging valve part to coordinate Withdirection of pump rotaextending through a wall of the tank for actuating said control valve.-

.7. In a unit of the type defined, in combination, a tank for hydraulic liquid, a rotary pump submerged in the liquid and having a shaft passing through aside wall of the tank, an inlet duct and a discharge duct carried by and extending from said pump and interchangeable in us'e'when the shaft rotation is reversed, said wall being removable and mounting said pump, the wall being symmetrical about central vertical and horizontal axes to permit of rotation in the plane of the wall, said ducts having symmetrical outlets displaced 180 whereby the one acting as discharge may be'positioned upwardly while the inlet is positioned near the'bottom of the tank;

8. The unit as defined 'in claim 7in which the "removable wall is a substantially vertical wall,

a removable top cover platefor theitank, a control valve for the pumpedliquid, means mounting said valve on and beneath. the said cover plate, ports in said cover plate and integral passages in the cover plate connecting said ports to said valve.

9. The unit as defined in claim 8 in which the valve is fitted with a depending inlet pipe disposed near a wall of the tank which abuts said vertical wall, said pump ducts being so offset that the outlet of the discharge duct cooperates with said inlet pipe.

10. In a uni-t of the type described, in combination, a tank for hydraulic liquid, a reversible rotary type pump submerged in said liquid near the bottom of said tank, at least a portion of one side wall of said tank being removable, means mounting said pump on said wall, a shaft for said pump extending through said wall, fastenings securing said Wall to said tank, said wall and the fastening disposition being symmetrical about 90 axes through the center of the wall whereby the wall may be applied to the tank in either of two positions 180 displaced in the plane of the wall, and two passages for said pump each having a terminal port, said ports being symmetrically disposed in respect to said axes.

11. In a unit of the type described, in combination, a tank for hydraulic liquid, a reversible rotary type pump submerged in said liquid near the bottom of said tank, at least a portion of one wall of said tank being removable, means mounting said ump on said wall, a shaft for said pump extending through said wall, fastenings securing said wall to said tank, said wall and the fastening disposition being symmetrical about 90 axes through the center of the wall whereby the wall may be applied to the tank in either of two positions 180 displaced in the plane of the wall, two passages for said pump each having a terminal port, said ports being symmetrically disposed in respect to said axes, a second removable wall for said tank, a control valve mounted on said second wall within said tank, an inlet passage for said valve, a tube extending from said passage and engaging with the pump terminal port positioned for the purpose and means to actuate said valve extending through said last mentioned removable wall.

12. The unit as defined in claim 11 in which the second removable wall includes integral ducts for conducting liquid from the valve to external circuits.

' 13. The unit as defined .in in claim 11 in which the first removable wall is a side wall and the second is the top of the tank, the pump ports bein directed up and down respectively, the downwardly directed port extending close to the bottom of the tank.

14. In a tank, pump and valve assembly, in combination, a closed tank, a removable cover for the tank, a pump secured to the tank and adapted to pump liquid therefrom, a manually operable control valve unit mounted on the inside of the cover, separable means connecting said pump and said unit to handle all the liquid delivered by said pump, said unit adapted to discharge by-passed liquid, relieved liquid and liquid returned thereto at low pressure to said tank for reuse, a manifold on said valve unit to collect all of said liquid to be discharged, a delivery pipe receiving said liqbid from the manifold, said pipe being arranged to deliver said liquid below the level of that in the tank and directly against a side wall thereof to increase the rate of cooling of the liquid.

/ 15. The arrangement as defined in claim 14 in which the pumpinlet is remote from said delivery pipe outlet.

16. A tank and pump assembly including in combination, a tank, one side of said tank including a lower wall and an offset overhanging upper wall, said lower wall being removable and adapted to be received in either of two positions on the tank displaced, a reversible rotary pump mounted on the inner face of saidremovable wall and having a shaft extending normally through the wall, a hub surrounding the shaft outside of and integral with the wall, a mounting flange on said hub to support the assembly, and the pump having two symmetrical passages 180 displaced adaptedto be interchangeably inlet and discharge dependent upon the direction of rotation of the pump.

17. A tank and pump and valve assembly including in combination, a tank, one side of said tank including a lower wall and an offset overhanging upper wall, said lower wall being removable and adapted to be received in either of two positions on the tank 180 displaced, a reversible rotary pump mounted on the inner face of said removable wall and having .a shaft extending normally through the wall, a hub surrounding the shaft outside of and integral with the wall, a mounting flange on said hub to support the assembly, the pump having two symmetrical passages 180 displaced adapted to be interchangeably inlet and discharge dependent upon the direction of rotation of the pump, a valve mounted on the inner face of one wall of the tank and having an inlet duct having an end adapted to cooperate with the then active discharge of the pump.

18. In a tank, a-pump and valve assembly in combination, a tank having at least one wall removably secured thereto and adapted to be applied in either of two positions, a reversible rotary pump unit in the tank and having two passages interchangeable as inlet and discharge dependent upon the direction of rotation of the pump, a control valve unit in the tank adapted to receive liquid from the pump and control its delivery to a point remote from the tank, a rigid connection from the active pump discharge to the valve inlet, said pump unit being secured to said removable wall whereby the said connection may be caused to cooperate with the other pump passage when the direction of pump rotation is to be reversed.

19. The assembly as defined in claim 18 in which the valve unit collects all liquid to be returned to the tank and a delivery pipe for said collected liquid arranged to discharge against a fixed wall of the tank.

HERBERT H. SCHMIEL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,577,695 Davenport Mar. 23, 1926 1,893,125 Biszantz Jan. 3, 1933 2,294,798 Nelson Sept. 1, 1942 2,362,944 Stephens Nov. 14, 1944 2,393,406 Parsons Jan. 22, 1946 2,448,532 Kirkham Sept. '7, 1948 FOREIGN PATENTS Number Country Date 516,790 Great Britain 1940 

